package StudyCode.UI;

import javax.swing.*;
import java.awt.*;
import java.awt.font.FontRenderContext;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;

/**
 * @author lixiaoyao
 */
public class FontTest {
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			@Override
			public void run() {
				JFrame frame=new FontFrame();
				frame.setTitle("FontTest");
				frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
				frame.setVisible(true);
			}
		});
	}

}

class FontFrame extends JFrame {
	public FontFrame() {
		add(new FontComponent());
		pack();
	}
}

class FontComponent extends JComponent {
	private static final int DEFAULT_WIDTH = 300;
	private static final int DEFAULT_HEIGHT = 200;

	protected void paintComponent(Graphics graphics) {
		Graphics2D graphics2D = (Graphics2D) graphics;

		String message = "Hello,World";

		Font font = new Font("Serif", Font.BOLD, 36);
		graphics2D.setFont(font);

		// measure the size of the message

		FontRenderContext context = graphics2D.getFontRenderContext();
		Rectangle2D bounds = font.getStringBounds(message, context);

		// set(x,y) = top left corner of text
		double x = (getWidth() - bounds.getWidth()) / 2;
		double y = (getHeight() - bounds.getHeight()) / 2;

		// add ascent to y to reach the baseline

		double ascent = -bounds.getY();
		double baseY = y + ascent;

		// draw the message

		graphics2D.drawString(message, (int) x, (int) baseY);

		graphics2D.setPaint(Color.LIGHT_GRAY);

		// draw the baseline

		graphics2D.draw(new Line2D.Double(x, baseY, x + bounds.getWidth(), baseY));

		// draw the enclosing rectangle

		Rectangle2D rectangle2D = new Rectangle2D.Double(x, y, bounds.getWidth(), bounds.getHeight());
		graphics2D.draw(rectangle2D);
	}

	public Dimension getPreferredSize() {
		return new Dimension(DEFAULT_WIDTH, DEFAULT_HEIGHT);
	}
}
